1. Field of Invention
The present invention relates to a method of manufacturing a thin film magnetic head having at least an inductive-type magnetic transducer for writing.
2. Description of Related Art
Recently, improvements in the performance of thin film magnetic heads, has been sought in accordance with an increase in the surface recording density of a hard disk drive. A composite thin film magnetic head, which has a stacked structure comprising a recording head having an inductive-type magnetic transducer for writing and a reproducing head having a magnetoresistive (hereinafter referred to as MR) element for reading, is widely used as the thin film magnetic head. MR elements include an AMR element using an anisotropic magnetoresistive (hereinafter referred to as AMR) effect, and a GMR element using a giant magnetoresistive (hereinafter referred to as GMR) effect. A reproducing head using the AMR element is called an AMR head or simply an MR head, and a reproducing head using the GMR element is called a GMR head. The AMR head is used as the reproducing head having a surface recording density of more than 1 gigabit per square inch, and the GMR head is used as the reproducing head having a surface recording density of more than 3 gigabits per square inch.
The composite thin film magnetic head having the recording head and the reproducing head as described above is manufactured through a plurality of manufacturing steps such as a sputtering step, a photolithography step, an electroplating step, an etching step and a polishing step. The above-mentioned electroplating step and etching step, in particular, also require a step of forming a photoresist pattern for serving as a mask to be used to selectively grow a plated film, an etching mask for serving as a mask to be used to selectively perform an etching process, and so on.
A series of processes of manufacturing the thin film magnetic head including a variety of steps as described above has a problem that the manufacturing lead time required for manufacturing becomes longer. Therefore, specific means for improving, such as reducing the number of steps, is required in order to realize further reductions of the manufacturing lead time for mass-production.
The invention is designed to overcome the foregoing problem. It is an object of the invention to provide a method of forming a magnetic layer pattern and a method of manufacturing a thin film magnetic head, which can reduce the number of manufacturing steps and thus reduce the manufacturing time.
The method of forming a magnetic layer pattern of the invention for forming the magnetic layer pattern on a surface of a predetermined underlayer includes: a first step of forming a frame pattern having an opening with a predetermined shape on the underlayer; a second step of forming at least a precursory magnetic layer as a preparatory layer for the magnetic layer pattern so as to cover at least a region including the opening of the frame pattern; and a third step of forming the magnetic layer pattern by polishing at least the precursory magnetic layer until at least the frame pattern is exposed.
In the method of forming a magnetic layer pattern of the invention, in the first step, a frame pattern having an opening with a predetermined shape is formed on a predetermined underlayer; in the second step, at least a precursory magnetic layer is formed so as to cover at least a region including the opening of the frame pattern; and in the third step, the magnetic layer pattern is formed on the predetermined underlayer by polishing the precursory magnetic layer until at least the frame pattern is exposed.
In the method of forming a magnetic layer pattern of the invention, preferably, a nonmagnetic material is used as a material of the frame pattern.
In the method of forming a magnetic layer pattern of the invention, the second step may include the steps of: forming a plurality of precursory magnetic layers; and forming a precursory nonmagnetic layer between the plurality of precursory magnetic layers; and the third step may include polishing the plurality of precursory magnetic layers and the precursory nonmagnetic layer.
According to a first aspect of the invention, a method of manufacturing a thin film magnetic head including two magnetic layers magnetically coupled to each other and having two magnetic poles, which face each other with a gap layer in between, in a recording-medium-facing surface, a thin film coil portion provided between the two magnetic layers, and an insulating layer for insulating the thin film coil portion from the two magnetic layers includes: a first step of forming a frame pattern with an opening having a predetermined shape on a predetermined underlayer; a second step of forming a precursory magnetic layer as a preparatory layer for a magnetic layer pattern forming at least part of the two magnetic layers, so as to cover at least a region including the opening of the frame pattern; and a third step of forming at least part of the two magnetic layers by polishing the precursory magnetic layer until at least the frame pattern is exposed.
In the method of manufacturing a thin film magnetic head according to the first aspect of the invention, in the first step, a frame pattern having an opening with a predetermined shape is formed on a predetermined underlayer; in the second step, a precursory magnetic layer is formed so as to cover at least a region including the opening of the frame pattern; and in the third step, at least part of the two magnetic layers is formed by polishing the precursory magnetic layer until at least the frame pattern is exposed.
According to a second aspect of the invention, a method of manufacturing a thin film magnetic head including: a first magnetic layer and a second magnetic layer magnetically coupled to each other and having two magnetic poles which face each other with a gap layer in between, in a recording-medium-facing surface to be faced with a recording medium, a thin film coil portion provided between the two magnetic layers, an insulating layer for insulating the thin film coil portion from the two magnetic layers, and a nonmagnetic layer and a third magnetic layer which are provided on the side opposite to the first magnetic layer with respect to the second magnetic layer includes: a first step of forming the third magnetic layer on an underlayer; a second step of forming a frame pattern with an opening having a predetermined shape on the third magnetic layer; a third step of forming a precursory nonmagnetic layer as a preparatory layer for the nonmagnetic layer and then forming a precursory magnetic layer as a preparatory layer for the second magnetic layer, so as to cover at least a region including the opening of the frame pattern; and a fourth step of forming the nonmagnetic layer and the second magnetic layer by polishing the respective surfaces of the precursory nonmagnetic layer and the precursory magnetic layer until at least the frame pattern is exposed.
In the method of manufacturing a thin film magnetic head according to the second aspect of the invention, in the first step, the third magnetic layer is formed on a predetermined underlayer; in the second step, a frame pattern having an opening with a predetermined shape is formed on the third magnetic layer; in the third step, a precursory nonmagnetic layer and then a precursory magnetic layer are formed so as to cover at least a region including the opening of the frame pattern; and in the fourth step, the nonmagnetic layer and the second magnetic layer are formed by polishing the respective surfaces of the precursory nonmagnetic layer and the precursory magnetic layer until at least the frame pattern is exposed.
In the method of manufacturing a thin film magnetic head according to the second aspect of the invention, the third magnetic layer may be formed by growing a plated film and both the precursory nonmagnetic layer and the precursory magnetic layer may be formed by sputtering, or both the third magnetic layer and the precursory magnetic layer may be formed by growing a plated film and the precursory nonmagnetic layer may be formed by sputtering.
According to a third aspect of the invention, a method of manufacturing a thin film magnetic head including a first magnetic layer and a second magnetic layer magnetically coupled to each other and having two magnetic poles which face each other with a gap layer in between, in a recording-medium-facing surface, a thin film coil portion provided between the two magnetic layers, an insulating layer for insulating the thin film coil portion from the two magnetic layers, and a nonmagnetic layer and a third magnetic layer which are provided on the side opposite to the first magnetic layer with respect to the second magnetic layer, includes: a first step of forming a frame pattern having an opening with a predetermined shape on a predetermined underlayer; a second step of forming a first precursory magnetic layer as a preparatory layer for the third magnetic layer, then forming a precursory nonmagnetic layer as a preparatory layer for the nonmagnetic layer, and then forming a second precursory magnetic layer as a preparatory layer for the second magnetic layer, so as to cover at least a region including the opening of the frame pattern; and a third step of forming the third magnetic layer, the nonmagnetic layer and the second magnetic layer by polishing the first precursory magnetic layer, the precursory nonmagnetic layer and the second precursory magnetic layer until at least the frame pattern is exposed.
In the method of manufacturing a thin film magnetic head according to the third aspect of the invention, in the first step, a frame pattern having an opening with a predetermined shape is formed on a predetermined underlayer; in the second step, a first precursory magnetic layer, then a precursory nonmagnetic layer and then a second precursory magnetic layer are formed so as to cover at least a region including the opening of the frame pattern; and in the third step, the third magnetic layer, the nonmagnetic layer and the second magnetic layer are formed by polishing the first precursory magnetic layer, the precursory nonmagnetic layer and the second precursory magnetic layer until at least the frame pattern is exposed.
In the method of manufacturing a thin film magnetic head according to the third aspect of the invention, the first precursory magnetic layer may be formed by growing a plated film and both the precursory nonmagnetic layer and the second precursory magnetic layer may be formed by sputtering, or both the first precursory magnetic layer and the second precursory magnetic layer may be formed by growing a plated film and the precursory nonmagnetic layer may be formed by sputtering.
In the method of manufacturing a thin film magnetic head according to the first, second and third aspects of the invention, layers capable of magnetically shielding the second magnetic layer may be used as the nonmagnetic layer and the third magnetic layer.
In the method of manufacturing a thin film magnetic head according to the first, second and third aspects of the invention, a predetermined nonmagnetic material may be used as a material of the frame pattern. In this case, preferably, a material containing either aluminum oxide or silicon oxide is used as the nonmagnetic material.
In the method of manufacturing a thin film magnetic head according to the first, second and third aspects of the invention, preferably, the frame pattern is formed by reactive ion etching.
In the method of manufacturing a thin film magnetic head according to the first, second and third aspects of the invention, a material containing either nickel iron or iron nitride may be used as a material of at least part of the first magnetic layer and the second magnetic layer, or a material containing an amorphous alloy may be used as a material of at least part of the first magnetic layer and the second magnetic layer. Preferably, either a cobalt-iron alloy or a zirconium-cobalt-iron alloy is used as the amorphous alloy.
Other and further objects, features and advantages of the invention will appear more fully from the following description.